There are a few ways to get into Sentosa island and all methods entail the payment of an entrance fee. The cheapest way is to walk from Vivocity along the newly-opened boardwalk parallel to the bridge linking Singapore to the island of Sentosa. To enter the island you only need to pay $1 to get through the turnstiles. Once in there you can avail yourself to the free transportation (bus, monorail and trams).
What is there on Sentosa Island - the playground of tourists and the home of the rich who own property worth a few million dollars in Sentosa Cove? See for yourself.